Related Experiment Video
Updated: Aug 19, 2025

Point-Of-Care Ultrasound Screening for Proximal Lower Extremity Deep Venous Thrombosis
Published on: February 10, 2023
'Dense Inverted Triangle Sign' in Cerebral Venous Thrombosis
Akiyuki Hiraga1, Yutaka Watabe1, Satoshi Kuwabara2
1Department of Neurology, Chiba Rosai Hospital, Japan.
Abstract:
The early diagnosis of cerebral venous thrombosis in the emergency department is challenging. A 70-year-old man presented to the emergency department after falling with new-onset convulsions. Brain unenhanced computed tomography (CT) revealed right frontal hemorrhage indicative of traumatic subarachnoid hemorrhage (SAH). Brain unenhanced CT on day 2 revealed increased density in the anterior superior sagittal sinus (SSS), namely 'dense inverted triangle sign.' Brain magnetic resonance venography showed a filling defect in the anterior SSS. When interpreting unenhanced brain CT findings in the setting of acute convulsions or cortical stroke, including SAH, cerebral sinus abnormalities near stroke foci should be evaluated carefully.
Related Concept Videos
Venous Thrombosis II: Clinical Manifestations and Diagnostic Studies
Venous Thrombosis III: Interprofessional Care
Venous Thrombosis I: Introduction
Veins of Head and Neck
On the other hand, the vertebral veins, unlike their arterial counterparts, are not primarily responsible for brain drainage. Instead, they drain the cervical vertebrae, spinal cord, and some small...
Anatomy of the Brain: Ventricles
Arteries of the Head and Neck
The internal carotid arteries supply blood to the anterior portion of the cerebrum. They enter the...

